Muscle tenderness score in temporomandibular disorders patients: A case-control study

Background: The total tenderness score (TTS) is commonly used in headache practice and contributes valuable information. Objective: To assess muscle tenderness scores in patients diagnosed with Temporomandibular disorders (TMD) and analyse their associations with various demographic and clinical parameters. Methods: Masticatory (MTS), cervical (CTS) and TTSs were analysed in this case-control study among 192 TMD patients and 99 controls. The study included a questionnaire and a clinical examination following RDC/TMD guidelines. Data were analysed using: Pearson's chi-square, analysis of variance, t test and Bonferroni post hoc. To examine the factors associated with MTS score in a multivariate manner, a conceptual hierarchical multiple regression model was adopted. Results: Masticatory and TTS differed between TMD sub-groups and controls. Muscle tenderness was positively associated with: female sex, whiplash history, parafunction, co-morbid pains such as headaches and body pain, pain intensity, onset, frequency and duration. In the conceptual hierarchical multiple regression model, pain onset, frequency and duration, co-morbid pains were mediators in the relationship between TMD diagnosis and MTS. Conclusion: Muscle tenderness scores were positively associated with TMD disease characteristics and co-morbid pain conditions, which may reflect associations with disease severity. MTS differed between TMD populations and may be used in routine patient workup, to assess MMD severity and changes over time as well as treatments response and as a research tool. MTS can be used as a common methodology to describe both headaches and masticatory muscle disorders and to facilitate interprofessional research and crosstalk between a headache and oro-facial pain practitioners.